package com.hmdp.utils;

import cn.hutool.core.lang.UUID;
import org.springframework.core.io.ClassPathResource;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.data.redis.core.script.DefaultRedisScript;

import java.util.Collections;
import java.util.concurrent.TimeUnit;

public class SimpleRedisLock implements ILock{
    private String name;
    private StringRedisTemplate stringRedisTemplate;

    private static final DefaultRedisScript<Long> UNLOCK_SCRIPT;
    static {
        UNLOCK_SCRIPT = new DefaultRedisScript<>();
        UNLOCK_SCRIPT.setLocation(new ClassPathResource("unlock.lua"));
        UNLOCK_SCRIPT.setResultType(Long.class);
    }

    public SimpleRedisLock(String name, StringRedisTemplate stringRedisTemplate) {
        this.name = name;
        this.stringRedisTemplate = stringRedisTemplate;
    }

    private static final String keyPreFix = "lock:";
    private static final String ID_PreFix = UUID.randomUUID().toString(true);
    @Override
    public boolean trylock(long timeoutSec) {
        //获取线程标识
        String threadId = ID_PreFix+Thread.currentThread().getId();

        //获取锁
        Boolean success = stringRedisTemplate.opsForValue()
                .setIfAbsent(keyPreFix+name, threadId, timeoutSec, TimeUnit.SECONDS);
        return Boolean.TRUE.equals(success);
    }
    @Override
    public void unlock() {
        //基于Lua脚本做这一部分
        //lua脚本的调用
        stringRedisTemplate.execute(UNLOCK_SCRIPT, Collections.singletonList(keyPreFix+name)
        ,ID_PreFix+Thread.currentThread().getId());

    }

//    @Override
//    public void unlock() {
//        //获取线程标识，
//        String threadId = ID_PreFix+Thread.currentThread().getId();
//        //获取锁中的标识
//        String lockId = stringRedisTemplate.opsForValue().get(keyPreFix + name);
//
//        //判断是否一致
//        if (threadId.equals(lockId)){
//            stringRedisTemplate.delete(keyPreFix+name);
//        }
//
//    }
}
